DE102009053406A1 - Method for the spatially resolved enlargement of nanoparticles on a substrate surface - Google Patents

Abstract

The invention relates to methods for spatially resolved magnification and size fine adjustment of precious metal nanoparticles on a substrate surface and the nanoparticle assemblies and nanostructured substrate surfaces thus prepared and their use. Specifically, the present invention relates to a method of spatially resolved magnification of noble metal nanoparticles present on a substrate comprising the steps of: a) providing a substrate coated with noble metal nanoparticles, b) optionally functionalizing the substrate with an agent which c) contacting the substrate with a noble metal salt solution, d) UV irradiation of the substrate in contact with the noble metal salt solution, thereby reducing the noble metal salt and electroless deposition of elemental noble metal on the noble metal nanoparticles and causing appropriate growth of the noble metal nanoparticles in the irradiated areas of the substrate, and e) optionally using a mask to cause localized growth of the noble metal nanoparticles in predetermined areas of the substrate.

Description

The present invention relates to methods for spatially resolved magnification and size fine tuning of noble metal nanoparticles on a substrate surface, and to the nanoparticle assemblies and nanostructured substrate surfaces so prepared and their use.

In recent years, nanostructures, especially ordered structures of noble metal nanoparticles on substrate surfaces, have found great interest in a variety of applications in various fields. For example, gold nanoparticles can be used in biochemical sensors ( Dyckman and Bogatyrev (2007), Russian Chemical Reviews 76 (2), 181-194 ) and as etching masks for the production of biomimetic interfaces and interfaces ( Lohmüller et al. (2008), NANO LEITERS 8 (5): 1429-1433 ).

For many of these applications it would be highly desirable to be able to set the size of these nanoparticles as precisely as possible locally and on a nanometer scale on macroscopic substrates. For example, larger linker molecules and hence more desired target molecules could be bound to larger nanoparticles and this capacity used to produce concentration gradients of a given antigen on a substrate. So z. For example, concentration-sensitive biochips can be produced in a simple manner. Even for the above-mentioned use as etching masks, a fine adjustment of the particle size with high spatial resolution would be very advantageous. Such a fine adjustment would allow, for example, the production of complex nano-optical elements such as Fresnel lenses and zone plates. Ordered areas of noble metal nanoparticles with given diameters could also be advantageously used in new transistors ( Sato et al. (1997), American Institute of Physics 82 (2), 696-702 ) or for fluorescence quenching ( Fan et al. (2003), PNAS, 100 (1), 6297-6301 ) be used.

The size of noble metal nanoparticles, in particular gold nanoparticles, can in principle before application to the substrate surface, for. B. when using. Metal colloids ( Kimling et al. (2006) J. Phys. Chem. B., 110, 15700-15707 ), or after application, for. By electroless deposition using a reducing agent ( Hrapovic et al. (2007), Langmuir 19: 3958-3965 ). In these methods described in the prior art, however, only a limited size adjustment is possible and above all no spatially resolved adjustment of the nanoparticle size.

In the German patent application DE 10 2007 017 032 and the corresponding international application PCT / EP2008 / 0071981 For example, methods for generating interparticle distance and particle size gradients in gold nanoparticle arrays made by micellar block copolymer nanolithography (BCML) are described. In these methods, particle size gradients are generated either by electroless deposition from a solution containing elemental gold as above, but varying the rate at which a nanoparticle-coated substrate surface is withdrawn from this solution or by irradiation with a laterally intensity-modulated light field.

However, these methods are not yet completely satisfactory and suitable for all applications, since it is difficult to produce several regions with widely differing average diameters of the nanoparticles and high spatial resolution side by side.

It has thus been a primary object of the present invention to provide improved methods of spatially resolved magnification and size fine tuning of noble metal nanoparticles on a substrate surface, which may involve very sharp particle size gradients or nanoparticle arrays comprising multiple regions of widely differing nanoparticle mean diameters and high spatial resolution juxtaposed, can be made in a simple and efficient way. A related task was to provide the appropriate nanoparticle assemblies and nanostructured substrate surfaces. A further object was the provision of the nanoparticle arrangements and nanostructured substrate surfaces produced according to the invention for various uses which hitherto were out of the question for such noble metal nanoparticle arrangements owing to the inadequate or inappropriately possible quantitative precision of noble metal nanoparticles on a substrate surface.

According to the invention, it has now been found that the above-mentioned main object can be achieved by providing the method according to claim 1, in which a substrate coated with (preferably fixed) noble metal nanoparticles is contacted with a noble metal salt solution and localized by UV irradiation of certain predetermined areas and controlled enlargement of the nanoparticles in these areas is initiated. The above-mentioned further objects are achieved by providing the nanoparticle assemblies and nanostructured substrate surfaces according to claims 17 and 18 and the Use according to claim 22 solved. More specific embodiments and other aspects of the present invention are the subject of the further claims.

Description of the invention

• a) Bereitstellung eines mit Edelmetall-Nanopartikeln beschichteten Substrats,
• b) gegebenenfalls Funktionalisierung des Substrats mit einem Agens, welches die Haftung der Edelmetall-Nanopartikel an dem Substrat unterstützt,
• c) Kontaktierung des Substrats mit einer Edelmetallsalzlösung,
• d) UV-Bestrahlung des Substrats in Kontakt mit der Edelmetallsalzlösung, wodurch eine Reduktion des Edelmetallsalzes und eine stromlose Abscheidung von elementarem Edelmetall auf den Edelmetall-Nanopartikeln und entsprechendes Wachstum der Edelmetall-Nanopartikel in den bestrahlten Bereichen des Substrats veranlasst wird,
• e) gegebenenfalls Verwendung einer Maske, um ein lokalisiertes Wachstum der Edelmetall-Nanopartikel in vorbestimmten Bereichen des Substrats zu veranlassen.

The present invention relates to a method for spatially resolved magnification of noble metal nanoparticles present on a substrate, comprising the following steps:

• a) providing a substrate coated with noble metal nanoparticles,
• b) optionally functionalizing the substrate with an agent which promotes adhesion of the noble metal nanoparticles to the substrate,
• c) contacting the substrate with a noble metal salt solution,
• d) UV irradiation of the substrate in contact with the noble metal salt solution, thereby causing reduction of the noble metal salt and electroless deposition of elemental noble metal on the noble metal nanoparticles and corresponding growth of the noble metal nanoparticles in the irradiated areas of the substrate,
• e) optionally using a mask to cause localized growth of the noble metal nanoparticles in predetermined areas of the substrate.

The provision of a substrate coated with noble metal nanoparticles in the above step a) can in principle be carried out by all methods known in the prior art. For example, a noble metal colloid layer can be applied to the substrate surface (cf. Hrapovic et al. above). Another preferred method according to the invention, if ordered nanoparticle structures are to be provided, is the production of a noble metal nanoparticle arrangement on a substrate by micellar nanolithography, in particular micellar block copolymer nanolithography (BCML) (see, for example, US Pat. EP 1 027 157 ). In micellar block copolymer nanolithography, a micellar solution of a block copolymer is deposited on a substrate, e.g. As by dip coating, and forms under suitable conditions on the surface of an ordered film structure of chemically different polymer domains, which depends inter alia on the type, molecular weight and concentration of the block copolymer. The micelles in the solution can be loaded with inorganic salts, which can be reduced to inorganic nanoparticles after deposition with the polymer film. To remove the polymer is usually a plasma treatment, for. B. with hydrogen plasma performed.

The substrate material used in the invention is basically not particularly limited and may include any material as long as it is stable under the conditions of the process of the present invention and does not interfere with or interfere with the reactions taking place. The substrate may be, for example, glass, SiO ₂ , silicon, metals (with or without passivated surfaces), semiconductor materials, e.g. GaAs, GaP, GaInP, AlGaAs, (optionally doped) metal oxides, e.g. ZnO, TiO ₂ , carbon (graphite, diamond), polymers, etc., and composite materials thereof. For some applications, transparent substrates such as glass or ITO on glass are preferred.

Also, the noble metal of the nanoparticles is not particularly limited and may include any noble metal known in the art for such nanoparticles, or composites of plural noble metals (hybrid particles) or mixtures of a noble metal with another metal. Preferably, the noble metal is selected from the group consisting of Au, Pt, Pd, Ag or mixtures / composites of these metals and most preferably is gold.

The original nanoparticles typically have diameters in the range of 1 nm to 100 nm, preferably 4 nm to 30 nm. The interparticle distances can be varied over a wide range, for example, in a range of 20 to 1000 nm, typically in the range of 30 up to 250 nm.

For carrying out the method according to the invention, it is important that good adhesion of the noble metal nanoparticles to the substrate surface is ensured. To improve the adhesion, therefore, the substrate may, if necessary, after the application of the nanoparticles, but before their enlargement, be treated with an agent which supports the adhesion of the nanoparticles. In particular, when using a coated with gold nanoparticles substrate surface of glass or silica, but also in Si, ZnO, TiO ₂ , GaAs surfaces and similar surfaces, it is preferable to treat the substrate with an agent which the adhesion of the Supported gold nanoparticles. It is preferably a silane, in particular selected from the group consisting of 3-aminopropyltriethoxysilane (APS), 3-mercaptopropyltriethoxysilane (MPS), N- [3- (trimethoxysilyl) propyl) ethylenediamine, 3- [2- (2 -Aminoethylamino) ethylamino] propyltrimethoxysilane, 3-aminopropyldimethylmethoxysilane, 3-aminopropyl) tris (trimethylsiloxy) silane and 3-mercaptopropyltrimethoxysilane.

In the noble metal salt solution, which in step c) brought into contact with the substrate surface In principle, it can be any metal salt solution which is suitable for UV-induced electroless deposition of the desired noble metal on the noble metal nanoparticles. In a preferred embodiment, this is an aqueous metal salt solution to which an organic compound has been added, which forms organic radicals during or after UV irradiation, which serve as a reducing agent for the noble metal ions. This organic compound is preferably selected from the group consisting of aldehydes, ketones or alcohols, in particular C ₁ -C ₁₀ -alcohols. More preferably, the C ₁ -C ₁₀ alcohol is selected from methanol, ethanol, propanol, butanol and ethylene glycol. The proportion of the organic compound may be readily adjusted by a person skilled in the art to vary the rate and extent of reduction by routine experimentation. Typically, the volume ratio of aqueous metal salt solution to organic compound will range from 100: 1 to 1: 2, more preferably 10: 1 to 1: 1, e.g. B. 3: 1 or 1: 1, lie.

In a specific embodiment, the noble metal salt solution is a gold salt solution, preferably a HAuCl ₄ solution.

The duration of UV irradiation may vary depending on the extent of nanoparticle enlargement desired and the particular substrate parameters, and a suitable irradiation time may readily be set by a person skilled in the art with routine experimentation. Typically, the UV irradiation is carried out for a duration in the range of 1 to 60 minutes, preferably 1 to 15 minutes, and at a wavelength in the range of 200 to 600 nm, preferably 200 to 400 nm.

Preferably, the method according to the invention is carried out such that the conditions of the UV irradiation for at least two. different regions of the substrate are varied so that at least two different regions with different average diameters of the noble metal nanoparticles are produced on the substrate. This variation of the conditions of UV irradiation is or includes, for example, a variation of the irradiation time.

In a preferred embodiment, the method of the invention is performed using a mask (step e)) to cause localized growth of the noble metal nanoparticles in predetermined regions of the substrate.

In a more specific embodiment, the mask has structures which allow diffraction of the irradiated UV light under suitable irradiation conditions, and the method is carried out under such conditions, in particular a suitable wavelength, that a diffraction pattern or pattern of brightness is formed on the substrate surface during the irradiation and the growth of noble metal nanoparticles is selectively induced in the more irradiated areas of the diffraction pattern or pattern of brightness.

These structures may include, for example, one or more pinhole apertures having a small hole diameter, preferably <100 μm, more preferably <10 μm, other diffraction gratings, diffraction edges, periodic patterns or gradients such as gradual gray filters. The pinhole diaphragms may, for example, have a circular, elliptical, rectangular or triangular shape.

According to the present invention, it is particularly preferable that the pinhole (n) has a circular diameter such that a diffraction pattern of concentric rings is formed on the substrate surface during irradiation, and the generated different regions having different mean diameters of the noble metal nanoparticles also become a pattern form concentric rings.

• f) Unterwerfen des Substrats mit der in den Schritten a)–e) nach einem der Ansprüche 1–12 entstandenen Edelmetall-Nanopartikelanordnung mindestens einem Ätzschritt, bei dem die Edelmetall-Nanopartikel als Ätzmaske wirken, womit durch selektive Ätzung in vorbestimmten Bereichen des Substrats unter Beibehaltung des Musters der Edelmetall-Nanopartikelanordnung eine gewünschte Reliefgestaltung der Substratoberfläche erzeugt wird. Bevorzugt wird dabei ein an das Substrat angepasstes Trockenätz-Verfahren verwendet. Im Falle von SiO₂ z. B. ein „Reactive Ion” Ätzschritt unter Verwendung eines fluorhaltigen Ätzgases. Geeignete Verfahren sind beispielsweise in Lohmüller et al. (2008), NANO LEITERS, Bd. 8, Nr. 5, 1429–1433 beschrieben. Jedoch können auch andere im Stand der Technik bekannte und für das jeweilige Substrat geeignete Ätzverfahren angewandt werden.

The present invention also relates to a method for producing a nanostructured substrate surface, comprising the steps a) -e) according to any one of claims 1-12 and also:

• f) subjecting the substrate to the in step a) -e) according to any one of claims 1-12 resulting noble metal nanoparticle assembly at least one etching step in which the noble metal nanoparticles act as an etch mask, thus selective etching in predetermined areas of the substrate while maintaining the pattern of the noble metal nanoparticle assembly, a desired relief design of the substrate surface is generated. In this case, a dry etching method adapted to the substrate is preferably used. In the case of SiO ₂ z. B. a "Reactive Ion" etching step using a fluorine-containing etching gas. Suitable methods are, for example, in Lohmüller et al. (2008), NANO LEITERS, Vol. 8, No. 5, 1429-1433 described. However, other etch techniques known in the art and suitable for the particular substrate may be used.

• f) Unterwerfen des Substrats mit der in den Schritten a)–e) nach Anspruch 13 entstandenen Edelmetall-Nanopartikelanordnung, bei der verschiedene Bereiche mit unterschied lichen mittleren Durchmessern der Edelmetall-Nanopartikel ein Muster konzentrischer Ringe bilden, mindestens einem Ätzschritt, bei dem die Edelmetall-Nanopartikel als Ätzmaske wirken, womit durch selektive Ätzung in vorbestimmten Bereichen des Substrats unter Beibehaltung des Musters von konzentrischen Kreisen eine Reliefgestaltung der Substratoberfläche erzeugt wird, die der einer Fresnel-Linse entspricht.

More specifically, this method comprises steps a) -e) according to claim 13 and further:

• f) subjecting the substrate to the resulting in steps a) -e) according to claim 13 noble metal nanoparticle assembly in which different areas with different union average diameters of the noble metal nanoparticles form a pattern of concentric rings, at least one etching step in which the noble metal -Nanopartikel act as an etching mask, whereby by selective etching in predetermined areas of the substrate while maintaining the pattern of concentric circles, a relief design of the substrate surface is generated, which corresponds to a Fresnel lens.

Further objects of the invention are the nanostructured substrate surfaces obtainable by the above methods and arrangements of noble metal nanoparticles on a substrate.

These arrangements typically comprise two or more distinct regions of noble metal nanoparticles having a mean diameter in the range of 5-200 nm, preferably 5-20 nm, and an average spacing in the range of less than 1 μm, preferably 30 to 250 nm, wherein in each of the different regions noble metal nanoparticles having a predetermined different average diameter are present.

In a specific and preferred embodiment, the arrangements are characterized in that the different regions with different mean diameters of the noble metal nanoparticles form one or more geometric patterns which are formed by diffraction of radiation at circular, elliptical, rectangular, triangular pinholes, edges or other periodically arranged patterns as well as gradients such as gradual gray filters resulting diffraction patterns or brightness patterns corresponds / correspond.

Particularly preferably, the various regions form a pattern of concentric rings.

The nanostructured substrate surfaces and arrangements of noble metal nanoparticles obtainable with the above inventive methods on a substrate form advantageous applications in a wide variety of fields due to the possibility of finely adjusting the particle size with high spatial resolution and precise representation of geometric patterns with several, sharply separated areas of different particle size.

Accordingly, another aspect of the present invention also relates to the use of these nanostructured substrate surfaces and devices in the fields of biochip technology, imaging technology, electronics, information processing, spectroscopy, sensor technology, optics, lithography.

Such a use is, for example, their use for the production of optical and electronic devices. In a more specific embodiment, the devices are selected from the group consisting of a mask, in particular a lithographic or photomask, a biochip, a sensor, an optical device, in particular a Fresnel lens, an optical grating, a microlens array or a transistor.

A further subject of the invention also relates to the devices themselves, which comprise such nanostructured substrate surfaces or arrangements. In a more specific embodiment, these devices are a mask, in particular a lithographic or photomask, a biochip, a sensor, an optical device, in particular a Fresnel lens, an optical grating, a microlens array or a transistor.

Brief description of the figures:

1 shows a schematic diagram for carrying out the method according to the invention with a provided by micellar nanolithography (BCML) gold nanoparticle assembly.

2 shows a gold nanoparticle arrangement directly after a BCML without further enlargement treatment of the particles (diameter of the nanoparticles: about 9 nm).

3 shows the result of an electroless deposition of gold without prior fixing (silanization) of the nanoparticles: Inhomogeneous particle growth and destruction of the order

4 shows gold nanoparticles after silanization and 2.5 minutes UV irradiation (diameter of nanoparticles: ca. 13 nm).

5 shows gold nanoparticles after silanization and 3 minutes UV irradiation (diameter of the nanoparticles: about 15 nm).

6 shows the localized growth of gold nanoparticles at 10 minutes UV irradiation using a mask with a circular pinhole (diameter about 1 mm); 6a : Overall view; 6b : Enlargement of the bright interior with strongly grown particles; 6c : Enlargement of the boundary area of indoor and outdoor space.

7 shows the localized growth of gold nanoparticles at 30 minutes UV irradiation using a shadow mask with a much smaller, circular aperture diameter than in 6 : Formation of a diffraction pattern with concentric rings; 7a : Overall view; 7b : enlarged ring structure of 7a ,

8th shows the localized growth of gold nanoparticles at 30 minutes UV irradiation using another circular shadow mask; 8a : Overall view; 8b -d; Magnifications of the area between the dark interior and the edge to the bright interior with greatly enlarged particles.

9 shows the localized growth of gold nanoparticles with detectable diffraction patterns at 10 minutes UV irradiation using a slightly elliptical shadow mask; 9a : Overall view; 9b -D: magnifications of a boundary.

The following examples are given to illustrate the present invention without, however, limiting it thereto.

EXAMPLE 1

Localized size growth of gold nanoparticles without diffraction patterns

The sample to be exposed consisting of SiO ₂ whose surface had gold nanoparticles with a mean diameter of about 9 nm ( 2 ) was treated with silane (gas phase deposition of 3-aminopropyltriethoxysilane (APS): Sample + 30 μL APS (in separate dish) in a desiccator for 30 minutes at 0.3 mbar, then 1 h at 80 ° C in the oven Exposure in a small container. To the vessel was added a 1: 1 mixture of 0.25% gold salt solution (HAuCl ₄ ) and ethanol. The amount of solution was measured so that the sample was covered by a liquid film about 1 mm high. Subsequently, UV was irradiated without a mask (commercial UV lamp, wavelength: 410 nm). Exposure times of 2 '30''gave particle diameter of about 13 nm ( 4 ); Exposure times of 3 'diameter of about 15 nm ( 5 ).

EXAMPLE 2

Generation of annular Fresnel diffraction structures

(F = Fresnel-Zahl, a = Blendenradius, L = Strecke Blende-Schirm, λ = Wellenlänge)Fresnel diffraction occurs when the following inequality is satisfied:

(F = Fresnel number, a = aperture radius, L = aperture diaphragm screen, λ = wavelength)

This condition is fulfilled in all subsequent experiments, so it is always Fresnel diffraction and not Fraunhoferbeugung.

The diffraction integral can not be solved analytically after application of the Fresnel approximation, but only numerically. The resulting diffraction pattern reacts extremely sensitive to the smallest changes in the distance or the aperture diameter. Since a realization of constant conditions (completely planar sample, completely planar mask, no "wave formation" of the solution,) can be realized only with great effort, a simpler (qualitative) approach was chosen for the subsequent experimental arrangements and images.

The sample to be exposed was placed in a small vessel. To the vessel was added a solution of 1.5 ml of 0.25% gold salt solution (HAuCl ₄ ) and 0.5 ml of ethanol. The amount of the solution was so dimensioned that the sample is covered by a ca. 1 mm high liquid film. The mask used was aluminum foil perforated with holes between 0.6 mm and 2 mm. This mask was placed about 1.1 mm above the sample. It was then exposed to UV light for 10 or 30 minutes.

6 shows the localized growth of gold nanoparticles at 10 minutes UV irradiation using a mask with a circular pinhole (approximate diameter: 1 mm). Here you can see very nice the lighter interior, which is clearly separated from the outside space with less grown particles. Here, however, no (at least not clear) further diffraction rings can be seen. This could be z. B. have been located at an unfavorable for the mask size exposure time.

9 shows the results using a slightly elliptical shadow mask and an exposure time of 10 minutes. Diffraction structures are visible and these were recorded with increasing magnification. Again, the relatively sharp demarcation of the individual rings becomes clear.

8th shows the results using a circular shadow mask and an exposure time of 30 minutes. The longer exposure time leads to a very strong growth in the exposed areas. This can be seen in particular at the overview shot (very bright ring structure). The area between the dark interior and the edge has been enlarged to a greatly enlarged area. The gold particles in the highest magnification ( 8d ) form a clearly recognizable edge. A purely qualitative determination of the size in the SEM leads to m radius of about 10 nm of the smaller (upper half of the picture) and about 17 nm of the larger particles (lower half of the picture).

7 shows the results using a further circular shadow mask and an exposure time of 30 minutes. Here again diffraction patterns can be seen. Again, the clearly demarcated ring structure is clearly visible.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102007017032 [0005]
• EP 2008/0071981 [0005]
• EP 1027157 [0010]

Cited non-patent literature

• Dyckman and Bogatyrev (2007), Russian Chemical Reviews 76 (2), 181-194 [0002]
• Lohmüller et al. (2008), NANO LEITERS 8 (5): 1429-1433 [0002]
• Sato et al. (1997), American Institute of Physics 82 (2), 696-702 [0003]
• Fan et al. (2003), PNAS, 100 (1), 6297-6301 [0003]
• Kimling et al. (2006) J. Phys. Chem. B., 110, 15700-15707 [0004]
• Hrapovic et al. (2007), Langmuir 19: 3958-3965 [0004]
• Hrapovic et al., [0010]
• Lohmüller et al. (2008), NANO LEITERS, Vol. 8, No. 5, 1429-1433. [0023]

Claims (25)

A method for spatially resolved magnification of noble metal nanoparticles present on a substrate, comprising the following steps: a) providing a substrate coated with noble metal nanoparticles, b) optionally functionalizing the substrate with an agent which promotes adhesion of the noble metal nanoparticles to the substrate, c) contacting the substrate with a noble metal salt solution, d) UV irradiation of the substrate in contact with the noble metal salt solution, thereby causing reduction of the noble metal salt and electroless deposition of elemental noble metal on the noble metal nanoparticles and corresponding growth of the noble metal nanoparticles in the irradiated areas of the substrate, e) optionally using a mask to cause localized growth of the noble metal nanoparticles in predetermined areas of the substrate. A method according to claim 1, characterized in that the noble metal is selected from the group consisting of gold, silver, palladium and platinum. A method according to claim 1 or 2, characterized in that the coated with noble metal nanoparticles substrate is provided by micellar block copolymer lithography (BCML) or by applying a noble metal colloid layer on the substrate surface. Method according to one of claims 1-3, characterized in that the substrate comprises a glass, Si, ZnO, TiO ₂ -GaAs, GaP, GaInP, AlGaAs or SiO ₂ surface and that the functionalization step b ) comprises a silanization. Process according to any one of claims 1-4, characterized in that the agent which assists the adhesion of noble metal nanoparticles to the substrate is a silane, in particular selected from the group consisting of 3-aminopropyltriethoxysilane (APS), 3-mercaptopropyltriethoxysilane (MPS), N- [3- (trimethoxysilyl) propyl) ethylenediamine, 3- [2- (2-aminoethylamino) ethylamino] propyltrimethoxysilane, 3-aminopropyldimethylmethoxysilane, 3-aminopropyl) -tris (trimethylsiloxy) silane and 3-mercaptopropyltrimethoxysilane. A method according to any one of claims 1-5, characterized in that the noble metal salt solution is an aqueous noble metal salt solution to which is further added an aldehyde, a ketone or an alcohol, preferably a C ₁ -C ₁₀ -alcohol. A method according to claim 6, characterized in that the C ₁ -C ₁₀ alcohol is selected from methanol, ethanol, propanol, butanol and ethylene glycol. Process according to any one of claims 1-7, characterized in that the noble metal salt solution is a HAuCl ₄ solution. Method according to any one of claims 1-8, characterized in that the UV irradiation is carried out for a duration in the range of 1 to 15 minutes and at a wavelength in the range of 200 to 600 nm. Method according to any one of claims 1-9, characterized in that the conditions of UV irradiation are varied for at least two different regions of the substrate so that at least two different regions with different mean diameters of the noble metal nanoparticles are produced on the substrate. A method according to claim 10, characterized in that the variation of the conditions of UV irradiation represents or comprises a variation of the irradiation duration. Method according to any one of claims 1-11, characterized in that step e) is carried out using a mask containing one or more apertured apertures with a hole diameter <10 μm, other diffraction gratings, diffraction edges or gradients such as graded gray filters, and under such conditions in that upon irradiation a diffraction pattern or pattern of brightness is formed on the substrate surface and the growth of the noble metal nanoparticles is selectively induced in the more irradiated areas of the diffraction pattern or pattern of brightness. A method according to claim 12, characterized in that step e) is carried out using a mask containing one or more apertured apertures with a hole diameter <10 μm of circular, elliptical, rectangular or triangular shape. A method according to claim 13, characterized in that the pinhole (n) has a circular diameter so that upon irradiation a diffraction pattern of concentric rings is formed on the substrate surface and the generated different regions having different mean diameters of the noble metal nanoparticles also form a pattern of concentric rings. A method for producing a nanostructured substrate surface, comprising the steps a) -e) according to any one of claims 1-13 and further comprising: f) subjecting the substrate to the noble metal resulting from steps a) -e) according to any one of claims 1-13. Nanoparticle arrangement at least one etching step in which the noble metal nanoparticles act as an etching mask, whereby by selective etching in predetermined areas of the substrate while maintaining the pattern of the noble metal nanoparticle assembly, a desired relief design of the substrate surface is generated. A method for producing a nanostructured substrate surface according to claim 15, comprising the steps a) - e) according to claim 14 and further: f) subjecting the substrate to the noble metal nanoparticle arrangement produced in steps a) -e) according to claim 14, in which different areas with different average diameters of the noble metal nanoparticles form a pattern of concentric rings, at least one etching step in which the noble metal nanoparticles Nanoparticles act as an etching mask, whereby by selective etching in predetermined areas of the substrate while maintaining the pattern of concentric circles a relief design of the substrate surface is generated, which corresponds to that of a Fresnel lens. A nanostructured substrate surface obtainable by the method of claim 15 or 16. Arrangement of noble metal nanoparticles on a substrate, the arrangement comprising two or more different regions of noble metal nanoparticles having an average diameter in the range of 5-200 nm, preferably 5-20 nm, and a mean spacing in the range of less than 1 micron , preferably from 30 to 250 nm, comprises, characterized in that in each of the different areas of noble metal nanoparticles are present with a predetermined different average diameter. Arrangement according to claim 18, characterized in that the different areas with different mean diameters of the noble metal nanoparticles form one or more geometrical patterns which, by diffraction of radiation at circular, elliptical, rectangular, triangular apertures, edges or other periodically arranged patterns as well as gradients such as gradual gray filters resulting diffraction patterns or brightness patterns corresponds / correspond. Arrangement according to claim 19, characterized in that the different areas form a pattern of concentric rings. Arrangement according to one of claims 18-20, characterized in that the noble metal nanoparticles are selected from the group of gold, silver, palladium and platinum nanoparticles or hybrid particles thereof. Use of the nanostructured substrate surface according to Claim 17 or the arrangement according to one of Claims 18-21 in the fields of biochip technology, imaging technology, electronics, information processing, spectroscopy, sensor technology, optics, lithography. Use according to claim 22 for producing a device selected from the group consisting of a mask, in particular a lithographic or photomask, a biochip, a sensor, an optical device, in particular a Fresnel lens, an optical grating, a microlens array or a Transistor includes. Apparatus comprising the nanostructured substrate surface of claim 17 or the assembly of any of claims 18-21. Apparatus according to claim 24, which is a mask, in particular a lithographic or photomask, a biochip, a sensor, an optical device, in particular a Fresnel lens, an optical grating, a microlens array or a transistor.

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